The present invention relates to a propylene polymer and its moldings, and also to a method for producing propylene polymers. Precisely, the invention relates to a propylene polymer of which the advantages are that its modulus of elasticity is well balanced with its melting point, that its low-temperature moldability and workability is good and that it has well-balanced mechanical strength; and relates to moldings obtained by molding the polymer; and also relates to a method for producing such propylene polymers. As having good low-temperature heat-sealability, good transparency, good scratch resistance and good mechanical strength, the propylene polymer of the invention is suitable to wrapping or packaging films.
Of polyolefins, polypropylene is inexpensive and has excellent physical properties, and its applications cover various fields including, for example, wrapping or packaging films, etc. For wrapping or packaging films, polypropylene must be modified to have improved low-temperature heat-sealability, as its melting point is relatively high. One general technique heretofore employed to meet the requirement comprises copolymerizing propylene with ethylene or with an xcex1-olefin having from 4 to 20 carbon atoms in the presence of a so-called Ziegler-Natta catalyst that comprises a titanium compound or a titanium compound held on a magnesium compound, and an organoaluminium compound.
However, it is known that the low-temperature heat-sealability of wrapping or packaging films of such a propylene-xcex1-olefin copolymer produced in that manner is not satisfactory though the transparency and the scratch resistance thereof are better than those of films of low-density polyethylene (Japanese Patent No. 268562, Japanese Patent Laid-Open Nos. 241439/1997, 255812/1990). If the xcex1-olefin content of the copolymer is increased so as to further improve the low-temperature heat-sealability of the copolymer, it involves some problems in that the composition distribution of the copolymer is broadened and the molecular weight thereof is lowered, and, as a result, the solvent-soluble content of the copolymer increases and the blocking resistance thereof is thereby lowered. Another problem is that the haze of the copolymer films increases, and the transparency thereof lowers.
On the other hand, it is reported that a metallocene catalyst is effective for producing polyolefins having a narrow molecular weight distribution (J. Polym. Sci., Polym. Chem., Ed. 23, 2117 (1985)). Having tried a metallocene catalyst, however, no one has succeeded in producing propylene polymers having well balanced low-temperature heat-sealability and mechanical strength. This is the current situation in the art.
The present invention is to provide a propylene polymer of which the advantages are that its modulus of elasticity is well balanced with its melting point, that its low-temperature moldability and workability is good and that it has well-balanced mechanical strength; and to provide moldings of the polymer and a method for producing the polymer.
We, the present inventors have assiduously studied so as to attain the above-mentioned object, and, as a result, have found that a propylene polymer of which the melting point and the enthalpy of fusion satisfy a specific relationship and of which the half-value width of the peak top of the elution curve obtained in programmed-temperature fractionation falls within a specific range attains the object. On the basis of this finding, we have completed the present invention. Specifically, the invention provides a propylene polymer and its moldings mentioned below, and provides a method for producing the propylene polymer also mentioned below.
1. A propylene polymer of which the heat of fusion xcex94H (J/g) and the melting point Tm (xc2x0 C.) measured through differential scanning calorimetry satisfy the following relationship:
xcex94Hxe2x89xa70.45xc3x97Tm+22.
2. The propylene polymer of above 1, which has the following properties (1), (2) and (3):
(1) Its melting point Tm (xc2x0 C.) measured through differential scanning calorimetry is 110xe2x89xa6Tmxe2x89xa6140;
(2) The half-value-width Th (xc2x0 C.) of the peak top of its elution curve obtained in programmed-temperature fractionation is Thxe2x89xa65;
(3) Its intrinsic viscosity [xcex7] (dl/g) measured in a solvent of tetralin at 135xc2x0 C. falls between 0.5 and 5.
3. The propylene polymer of above 2, of which the melting point Tm (xc2x0 C.) measured through differential scanning calorimetry is 120xe2x89xa6Tmxe2x89xa6140.
4. The propylene polymer of above 2, of which the melting point Tm (xc2x0 C.) measured through differential scanning calorimetry is 120xe2x89xa6Tmxe2x89xa6135.
5. The propylene polymer of any of above 1 to 4, which is a propylene homopolymer having an isotactic pentad fraction [mmmm] of from 65 to 85 mol %.
6. The propylene polymer of any of above 1 to 4, which is a propylene homopolymer having an isotactic pentad fraction [mmmm] of from 70 to 80 mol %.
7. A molding obtained by molding the propylene polymer of any of above 1 to 6.
8. A method for producing the propylene polymer of any of above 1 to 6, which comprises polymerizing propylene or propylene with ethylene and/or an xcex1-olefin having from 4 to 20 carbon atoms, in the presence of an olefin polymerization catalyst that contains (A) a transition metal compound of the Group 4 of the Periodic Table represented by the following general formula (1), and (B) at least one selected from (B-1) aluminiumoxy compounds and (B-2) ionic compounds capable of reacting with the transition metal compound to give cations: 
wherein R1 to R11, and X1 and x2 each independently represent a hydrogen atom, a halogen atom, a hydrocarbon group having from 1 to 20 carbon atoms, a halogen-containing hydrocarbon group having from 1 to 20 carbon atoms, a silicon-containing group, an oxygen-containing group, a sulfur-containing group, a nitrogen-containing group, or a phosphorus-containing group; R3 and R4, and R8 and R9 may be bonded to each other to form a ring; y1 is a divalent crosslinking group that crosslinks the two ligands, representing any of a hydrocarbon group having from 1 to 20 carbon atoms, a halogen-containing hydrocarbon group having from 1 to 20 carbon atoms, a silicon-containing group, a germanium-containing group, a tin-containing group, xe2x80x94Oxe2x80x94, xe2x80x94COxe2x80x94, xe2x80x94Sxe2x80x94, xe2x80x94SO2xe2x80x94, xe2x80x94NR12xe2x80x94, xe2x80x94PR12xe2x80x94, xe2x80x94P(O)R12xe2x80x94, xe2x80x94BR12xe2x80x94 or xe2x80x94AlR12xe2x80x94; R12 represents a hydrogen atom, a halogen atom, a hydrocarbon group having from 1 to 20 carbon atoms, or a halogen-containing hydrocarbon group having from 1 to 20 carbon atoms; M1 represents titanium, zirconium or hafnium.
9. A method for producing the propylene polymer of any of above 1 to 6, which comprises polymerizing propylene or propylene with ethylene and/or an xcex1-olefin having from 4 to 20 carbon atoms, in the presence of an olefin polymerization catalyst that contains (A) a transition metal compound of the Group 4 of the Periodic Table represented by the following general formula (2), and (B) at least one selected from (B-1) aluminiumoxy compounds and (B-2) ionic compounds capable of reacting with the transition metal compound to give cations: 
wherein M1 represents titanium, zirconium or hafnium; E1 and E2 each are a ligand selected from a cyclopentadienyl group, a substituted cyclopentadienyl group, an indenyl group, a substituted indenyl group, a heterocyclopentadienyl group, a substituted heterocyclopentadienyl group, an amido group, a phosphido group, a hydrocarbon group and a silicon-containing group, and they form a crosslinked structure via A1 and A2, and they may be the same or different; X3 represents a "sgr"-bonding ligand, and a plurality of X3""s, if any, may be the same or different, and it may be crosslinked with other X3, E1, E2 or Y2; Y2 represents a Lewis base, and a plurality of Y3""s, if any, may be the same or different, and it may be crosslinked with other Y2, E1, E2 or X3; A1 and A2 each are a divalent crosslinking group that crosslinks the two ligands, representing any of a hydrocarbon group having from 1 to 20 carbon atoms, a halogen-containing hydrocarbon group having from 1 to 20 carbon atoms, a silicon-containing group, a germanium-containing group, a tin-containing group, xe2x80x94Oxe2x80x94, xe2x80x94COxe2x80x94, xe2x80x94Sxe2x80x94, xe2x80x94SO2xe2x80x94, xe2x80x94NR12xe2x80x94, xe2x80x94PR12xe2x80x94, xe2x80x94P(O)R12xe2x80x94, xe2x80x94BR12xe2x80x94 or xe2x80x94AlR12xe2x80x94; R12 represents a hydrogen atom, a halogen atom, a hydrocarbon group having from 1 to 20 carbon atoms, or a halogen-containing hydrocarbon group having from 1 to 20 carbon atoms; and A1 and A2 may be the same or different; q is an integer of from 1 to 5, indicating [(valence of M1)xe2x88x922]; and r is an integer of from 0 to 3.
10. The method for producing the propylene polymer of above 8 or 9, wherein propylene or propylene with ethylene and/or an xcex1-olefin having from 4 to 20 carbon atoms is polymerized in a vapor phase.
11. The method for producing the propylene polymer of above 8 or 9, wherein propylene or propylene with ethylene and/or an xcex1-olefin having from 4 to 20 carbon atoms is polymerized in the presence of liquid propylene.
The invention is a propylene polymer and its moldings, and also a method for producing the propylene polymer mentioned above. More precisely, the invention relates to a propylene polymer of which the stereospecificity is on an intermediate level (for example, the stereospecificity of the polymer represented by the isotactic pentad fraction thereof is at most 85 mol %, preferably at most 80 mol %), which is not sticky and has a low melting point, and which is flexible (its tensile modulus falls between 600 and 1,600 MPa, preferably between 700 and 1,200 MPa, more preferably between 800 and 1,100 MPa); and relates to moldings of the polymer and to a method for producing the polymer.
The invention is described in detail hereinunder.
1. Propylene Polymer:
The propylene polymer of the invention is such that its heat of fusion xcex94H (J/g) and its melting point Tm (xc2x0 C.) measured through differential scanning calorimetry satisfy the following relationship:
xcex94Hxe2x89xa70.45xc3x97Tm+22.
Polymers not satisfying the requirement lose the balance of melting point and modulus of elasticity thereof, and lose the balance of moldability and workability and mechanical strength thereof. Films of such polymers are unfavorable since the balance of low-temperature heat-sealability and mechanical strength thereof is not good.
Preferably, xcex94H (J/g) and the melting point Tm (xc2x0 C.) of the propylene polymer of the invention satisfy the following relationship:
xcex94Hxe2x89xa70.45xc3x97Tm+25.
More preferably, the propylene polymer of the invention has the following properties (1), (2) and (3):
(1) Its melting point Tm (xc2x0 C.) measured through differential scanning calorimetry is 110xe2x89xa6Tmxe2x89xa6140;
(2) The half-value width Th (xc2x0 C.) of the peak top of its elution curve obtained in programmed-temperature fractionation is Thxe2x89xa65;
(3) Its intrinsic viscosity [xcfx81] (dl/g) measured in a solvent of tetralin at 135xc2x0 C. falls between 0.5 and 5.
If not satisfying the above-mentioned requirements, the polymer would hardly attain the object of the invention. For example, the polymer having Tm of lower than 110xc2x0 C. and therefore not satisfying the requirement (1) is inconvenient to the field of medicines and edibles as its products will fuse when boiled for sterilization. The polymer having Tm of higher than 140xc2x0 C. could not be a soft material. If not satisfying the requirement (2), the polymer contains an increased amount of sticky components and its films will be not good. The polymer having [xcfx81] of smaller than 0.5 dl/g and therefore not satisfying the requirement (3) is not so good as its mechanical strength will be low. The polymer having [xcfx81] of larger than 5.0 dl/g is also not so good as its moldability will be low.
Even more preferably, the propylene polymer of the invention has the following properties (1), (2), (3) and (4):
(1) Its heat of fusion xcex94H (J/g) and its melting point Tm (xc2x0 C.) measured through differential scanning calorimetry satisfy the following relationship:
xcex94Hxe2x89xa70.45xc3x97Tm+22;
(2) Its melting point Tm (xc2x0 C.) measured through differential scanning calorimetry is 120xe2x89xa6Tmxe2x89xa6135;
(3) The half-value width Th (xc2x0 C.) of the peak top of its elution curve obtained in programmed-temperature fractionation is Thxe2x89xa65;
(4) Its intrinsic viscosity [xcfx81] (dl/g) measured in a solvent of tetralin at 135xc2x0 C. falls between 0.5 and 5.
Preferably, Tm (xc2x0 C.) of the polymer is 120xe2x89xa6Tmxe2x89xa6140, more preferably 120xe2x89xa6Tmxe2x89xa6135. Also preferably, [xcfx81] of the polymer falls between 0.5 and 4 dl/g, more preferably between 1.0 and 3 dl/g.
The methods for measuring the parameters of the polymer are described in detail in the section of Examples given hereinunder.
In addition to the above-mentioned requirements, the molecular weight distribution (Mw/Mn) of the polymer measured through gel permeation chromatography is preferably at most 4, more preferably at most 3.5, even more preferably at most 3. If its molecular weight distribution (Mw/Mn) is larger than 4, the polymer will be sticky. Also preferably, the boiling diethyl ether extract of the polymer is at most 5% by weight. If its extract is larger than 5% by weight, the polymer will be sticky when formed into films. The method for measuring the boiling diethyl ether extract of the polymer is described in detail in the section of Examples given hereinunder. Also preferably, the peak top temperature Tp of the polymer measured through programmed-temperature fractionation falls between 60 and 95xc2x0 C. Also preferably, the component of the polymer that is eluted within a temperature range of Tpxc2x15xc2x0 C. accounts for at least 70% by weight of the polymer.
The propylene polymer of the invention may be a propylene homopolymer and may also be a copolymer of propylene with ethylene and/or an xcex1-olefin having from 4 to 20 carbon atoms (the copolymer is hereinafter referred to as a propylene copolymer). The xcex1-olefin having from 4 to 20 carbon atoms includes 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, etc. In the invention, one more or more of these may be used.
For the propylene homopolymer, its isotactic pentad fraction [mmmm] preferably falls between 65 and 85 mol %, more preferably between 70 and 80 mol %. The isotactic pentad fraction referred to herein is meant to indicate the isotactic fraction of the pentad units in the molecular chain of polypropylene, which is measured on the basis of the signals for the methyl groups in the 13C nuclear magnetic resonance spectrum of the polymer according to the proposal of A. Zambelli, et al. described in Macromolecules, 6, 925, 1973. The 13C nuclear magnetic resonance spectrometry of the polymer is effected by the use of the following apparatus under the condition mentioned below, based on the peak assignment proposed by A. Zambelli et al. in Macromolecules, 8, 687, 1975.
Apparatus: JEOL""s JNM-EX400 Model 13C-NMR
Method: proton complete decoupling
Concentration: 220 mg/ml
Solvent: 90/10 (by volume) mixed solvent of 1,2,4-trichlorobenzene and heavy benzene
Temperature: 130xc2x0 C.
Pulse width: 45xc2x0
Pulse frequency: 4 seconds
Frequency integration: 10,000 times
For the propylene copolymer, its comonomer content except propylene is preferably at most 1.0 mol %, in addition to the above-mentioned requirements. Also preferably, the stereospecificity index of the copolymer to be indicated by the isotactic triad fraction [mm] of the propylene moiety of the copolymer falls between 80 and 92 mol %. A larger value of the index means that the copolymer has a higher degree of stereospecificity. The copolymer having a stereospecificity index of smaller than 80 mol % could not be molded well as its elasticity will be too low. The copolymer having a stereospecificity index of larger than 92 mol % will be too hard and could not be flexible. The fraction [mm] can be obtained also through 13C-NMR, like the above-mentioned fraction [mmmm]. The method for measuring them is described in detail in the section of Examples given hereinunder. Preferably, the propylene copolymer has a random structure.
In ordinary propylene polymerization, the carbon atom on the side of the methylene in one propylene monomer compound first bonds to the active point of the polymerization catalyst used, and the other propylene monomer compounds are then coordinated in order in the same manner as before and are polymerized. This is so-called 1,2-insertion in ordinary propylene polymerization. Rarely, however, 2,1-insertion or 1,3-insertion (abnormal insertion) may occur in propylene polymerization. Preferably, the 2,1-insertion or 1,3-insertion seldom occurs in the polymerization to give the propylene polymer of the invention. Concretely, the abnormal insertion in the propylene polymerization in the invention preferably satisfies the following relational formula (1):
[(m-2,1)+(r-2,1)+(1,3)]xe2x89xa65.0 (%)xe2x80x83xe2x80x83(1)
wherein (m-2,1) means the meso-2,1 insert content (%) measured trough 13C-NMR; (r-2,1) means the racemi-2,1 insert content (%) measured through 13C-NMR; and (1,3) means the 1,3-insert content (%) measured through 13C-NMR.
More preferably, it satisfies the following relational formula (2):
[(m-2,1)+(r-2,1)+(1,3)]xe2x89xa61.0 (%)xe2x80x83xe2x80x83(2).
Most preferably, it satisfies the following relational formula (3):
[(m-2,1)+(r-2,1)+(1,3)]xe2x89xa60.1 (%)xe2x80x83xe2x80x83(3).
If the propylene polymerization does not satisfy the relational formula (1), the crystallinity of the polymer produced will be low beyond expectation, and the polymer will be sticky.
The insert contents (m-2,1), (r-2,1) and (1,3) are obtained in accordance with Grassi et al""s report (Macromolecules, 21, 617, 1988) and Busico et ales report (Macromolecules, 27, 7538, 1994). Concretely, based on their proposals, the assignment of the spectral peaks for the respective inserts is determined, and each insert content is obtained from the integrated intensity of each peak. Specifically, the value (m-2,1) is the meso-2,1 insert content (%) of the polymer analyzed, which is calculated from the ratio of the integrated intensity of the peak assigned to the Pxcex1,xcex3-thermo that appears at around 17.2 ppm, to the integrated intensity of the peaks appearing in the total methyl carbon region. The value (r-2,1) is the racemi-2,1 insert content (%) of the polymer analyzed, which is calculated from the ratio of the integrated intensity of the peak assigned to the Pxcex1,xcex3-thermo that appears at around 15.0 ppm, to the integrated intensity of the peaks appearing in the total methyl carbon region. The value (1,3) is the 1,3-insert content (%) of the polymer analyzed, which is calculated from the ratio of the integrated intensity of the peak assigned to the Txcex2,G+ that appears at around 31.0 ppm, to the integrated intensity of the peaks appearing in the total methyl carbon region.
In 13C-NMR spectrometry of the propylene polymer of the invention, it is more desirable that no peak assigned to the molecular chain terminal (n-butyl group) of the polymer derived from the 2,1-insertion appears in the spectral chart. For the molecular chain terminal derived from the 2,1-insertion, the 2,1-insert content of the polymer is calculated in accordance with Jungling et al""s report (J. Polym. Sci.: Part A: Polym. Chem., 33, 1305, 1995). Concretely, the assignment of the peak for the 2,1-insertion in the 13C-NMR chart of the polymer is determined, and the insert content is calculated from the integrated intensity of the peak. For isotactic polypropylene, the peak appearing at around 18.9 ppm is assigned to the carbon atom of the terminal methyl group of the n-butyl group. 13C-NMR to determine the abnormal insertion and the molecular chain terminal of the polymer may be effected by the use of the above-mentioned apparatus under the condition also mentioned above.
2. Method for Producing Propylene Polymer:
For producing the propylene polymer of the invention, propylene or propylene with ethylene and/or an xcex1-olefin having from 4 to 20 carbon atoms is polymerized in the presence of an olefin polymerization catalyst that contains (A) a transition metal compound of the Group 4 of the Periodic Table, and (B) at least one selected from (B-1) aluminiumoxy compounds and (B-2) ionic compounds capable of reacting with the transition metal compound to give cations.
First described are the constituent components of the olefin polymerization catalyst to be used in the invention, and the method for producing the catalyst.
The component (A) is a transition metal compound of the Group 4 of the Periodic Table, which is selected from the following group A.
The group A includes the following (A-1) and (A-2):
(A-1):
This is a transition metal compound of the Group 4 of the Periodic Table represented by the following general formula (1): 
wherein R1 to R11, and X1 and X2 each independently represent a hydrogen atom, a halogen atom, a hydrocarbon group having from 1 to 20 carbon atoms, a halogen-containing hydrocarbon group having from 1 to 20 carbon atoms, a silicon-containing group, an oxygen-containing group, a sulfur-containing group, a nitrogen-containing group, or a phosphorus-containing group; R3 and R4, and R8 and R9 may be bonded to each other to form a ring; Y1 is a divalent crosslinking group that crosslinks the two ligands, representing any of a hydrocarbon group having from 1 to 20 carbon atoms, a halogen-containing hydrocarbon group having from 1 to 20 carbon atoms, a silicon-containing group, a germanium-containing group, a tin-containing group, xe2x80x94Oxe2x80x94, xe2x80x94COxe2x80x94, xe2x80x94Sxe2x80x94, xe2x80x94SO2xe2x80x94, xe2x80x94NR12xe2x80x94, xe2x80x94PR12xe2x80x94, xe2x80x94P(O)R12xe2x80x94, xe2x80x94BR12xe2x80x94 or xe2x80x94AlR12xe2x80x94; R12 represents a hydrogen atom, a halogen atom, a hydrocarbon group having from 1 to 20 carbon atoms, or a halogen-containing hydrocarbon group having from 1 to 20 carbon atoms; M1 represents titanium, zirconium or hafnium.
The transition metal compound is a single-crosslinked complex.
In formula (1), the halogen atom for R1 to R11, and X1 and X2 includes chlorine, bromine, fluorine and iodine atoms. The hydrocarbon group having from 1 go 20 carbon atoms includes an alkyl group such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-hexyl and n-decyl groups; an aryl group such as phenyl, 1-naphthyl and 2-naphthyl groups; and an aralkyl group such as benzyl group. The halogen-containing hydrocarbon group having from 1 to 20 carbon atoms includes the above-mentioned hydrocarbon groups of which at least one hydrogen atom is substituted with a halogen atom, such as trifluoromethyl group. The silicon-containing group includes trimethylsilyl and dimethyl(t-butyl)silyl groups; the oxygen-containing group includes methoxy and ethoxy groups; the sulfur-containing group includes thiol and sulfonic acid groups; the nitrogen-containing group includes dimethylamino group; the phosphorus-containing group includes phenylphosphine group. R3 and R4, and R8 and R9 may be bonded to each other to form a ring such as fluorene. For specific examples of R3 and R4, and R8 and R9 bonding to each other, referred to are the groups mentioned above but excepting hydrogen atom. For R3 and R9, preferred are a hydrogen atom and an alkyl group having at most 6 carbon atoms; more preferred are a hydrogen atom, a methyl group, an ethyl group, an isopropyl group, and a cyclohexyl group; and even more preferred is a hydrogen atom. For R3, R4, R8 and R9, preferred is an alkyl group having at most 6 carbon atoms; more preferred are a methyl group, an ethyl group, an isopropyl group and a cyclohexyl group; and even more preferred is an isopropyl group. Preferably, R4, R5, R7, R9 and R10 are all hydrogen atoms. More preferably, R1 is an alkyl group and not a hydrogen atom, and R7 is a hydrogen atom. For X1 and X2, preferred are a halogen atom, a methyl group, an ethyl group and a propyl group. Specific examples of Y1 are methylene, ethylene, ethylidene, isopropylidene, cyclohexylidene, 1,2-cyclohexylene, dimethylsilylene, tetramethyldisilylene, dimethylgermylene, methylborylidene (CH3xe2x80x94Bxe2x95x90), methylalumilidene (CH3xe2x80x94Alxe2x95x90), phenylphosphylidene (Ph-Pxe2x95x90), phenylphosphorylidene (PhPOxe2x95x90), 1,2-phenylene, vinylene (xe2x80x94CHxe2x95x90CHxe2x80x94), vinylidene (CH2xe2x95x90Cxe2x95x90), methylimido, oxygen (xe2x80x94Oxe2x80x94), sulfur (xe2x80x94Sxe2x80x94). Of these, preferred are methylene, ethylene, ethylidene and isopropylidene for more favorably attaining the object of the invention.
M1 indicates titanium, zirconium or hafnium, and is preferably hafnium.
Specific examples of the transition metal compound of formula (1) are 1,2-ethanediyl(1-(2-isobutylindenyl))(2-indenyl)hafnium dichloride, 1,2-ethanediyl(1-(2-butylindenyl))(2-indenyl)hafnium dichloride, 1,2-ethanediyl(1-(2-butylindenyl))(2-(4,7-dimethylindenyl))hafnium dichloride, 1,2-ethanediyl (1-(2-isopropylindenyl))(2-(4,7-dimethylindenyl))hafnium dichloride, 1,2-ethanediyl(1-(2-isopropylindenyl))(2-(4,7-diisopropylindenyl))hafnium dichloride; dimethylsilylene(1-(2-isobutylindenyl))(2-indenyl)hafnium dichloride, dimethylsilylene(1-(2-butylindenyl))(2-indenyl)hafnium dichloride, dimethylsilylene(1-(2-butylindenyl))(2-(4,7-dimethylindenyl))hafnium dichloride, methylsilylene(1-(2-isopropylindenyl))(2-(4,7-dimethylindenyl))hafnium dichloride, methylsilylene(1-(2-isopropylindenyl))(2-(4,7-diisopropylindenyl))hafnium dichloride; 1,3-propanediyl(1-(2-isopropylindenyl))(2-indenyl)hafnium dichloride, 1,3-propanediyl(1-(2-isobutylindenyl))(2-indenyl)hafnium dichloride, 1,3-propanediyl(1-(2-butylindenyl))(2-indenyl)hafnium dichloride, 1,3-propanediyl(1-(2-butylindenyl))(2-(4,7-dimethylindenyl))hafnium dichloride, 1,3-propanediyl(1-(2-isopropylindenyl))(2-(4,7-dimethylindenyl))hafnium dichloride, 1,3-propanediyl(1-(2-isopropylindenyl))(2-(4,7-diisopropylindenyl))hafnium dichloride; 1,2-ethanediyl(1-(4,7-diisopropylindenyl))(2-(4,7-diisopropylindenyl))hafnium dichloride, 1,2-ethanediyl(9-fluorenyl)(2-(4,7-diisopropylindenyl))hafnium dichloride, isopropylidene(1-(4,7-diisopropylindenyl))(2-(4,7-diisopropylindenyl))hafnium dichloride, 1,2-ethanediyl(1-(4,7-dimethylindenyl))(2-(4,7-diisopropylindenyl))hafnium dichloride, 1,2-ethanediyl(9-fluorenyl)(2-(4,7-dimethylindenyl))hafnium dichloride, isopropylidene(1-(4,7-dimethylindenyl))(2-(4,7-diisopropylindenyl))hafnium dichloride, 1,2-ethanediyl(2-indenyl)(1-(2-isopropylindenyl))hafnium dichloride, dimethylsilylene-(2-indenyl)(1-(2-isopropylindenyl))hafnium dichloride; and also their derivatives derived from the compounds by substituting the hafnium therein with zirconium or titanium. However, these are not limitative.
The transition metal compound of formula (1) may be produced, for example, according to the method described in the applicant""s own prior patent application, Japanese Patent Laid-Open No. 130807/1999. Forthecomponent (A-1), two or more of the transition metal compounds may be combined.
(A-2):
This is a transition metal compound of Group 4 of the Periodic Table represented by the following general formula (2): 
wherein M1 represents titanium, zirconium or hafnium; E1 and E2 each are a ligand selected from a cyclopentadienyl group, a substituted cyclopentadienyl group, an indenyl group, a substituted indenyl group, a heterocyclopentadienyl group, a substituted heterocyclopentadienyl group, an amido group, a phosphido group, a hydrocarbon group and a silicon-containing group, and they form a crosslinked structure via A1 and A2, and they may be the same or different; X3 represents a xcfx81-bonding ligand, and a plurality of X3""s, if any, may be the same or different, and it may be crosslinked with other X3, E1, E2 or Y2; Y2 represents a Lewis base, and a plurality of Y2""s, if any, may be the same or different, and it may be crosslinked with other Y2, E1, E2or X3; A1 and A2 each are a divalent crosslinking group that crosslinks the two ligands, representing any of a hydrocarbon group having from 1 to 20 carbon atoms, a halogen-containing hydrocarbon group having from 1 to 20 carbon atoms, a silicon-containing group, a germanium-containing group, a tinxe2x80x94containing group, xe2x80x94Oxe2x80x94, xe2x80x94COxe2x80x94, xe2x80x94Sxe2x80x94, xe2x80x94SO2xe2x80x94, xe2x80x94NR12xe2x80x94, xe2x80x94PR12xe2x80x94, xe2x80x94P(O)R12xe2x80x94, xe2x80x94BR12xe2x80x94 or xe2x80x94AlR12xe2x80x94; R12 represents a hydrogen atom, a halogen atom, a hydrocarbon group having from 1 to 20 carbon atoms, or a halogen-containing hydrocarbon group having from 1 to 20 carbon atoms; and A1 and A2 may be the same or different; q is an integer of from 1 to 5, indicating [(valence of M1)xe2x88x922]; and r is an integer of from 0 to 3.
In the transition metal compound of formula (2) (this is hereinafter referred to as a double-crosslinked complex), M1 represents titanium, zirconium or hafnium, and is preferably zirconium or hafnium. E1 and E2 each are., as so mentioned hereinabove, a ligand selected from a cyclopentadienyl group, a substituted cyclopentadienyl group, an indenyl group, a substituted indenyl group, a heterocyclopentadienyl group, a substituted heterocyclopentadienyl group, an amido group (xe2x80x94N less than ), a phosphido group (xe2x80x94P less than ), a hydrocarbon group [ greater than CRxe2x80x94,  greater than C less than ] and a silicon-containing group [ greater than SiRxe2x80x94,  greater than Si less than ] (in which R is a hydrogen atom, or a hydrocarbon group having from 1 to 20 carbon atoms, or a hetero atom-containing group), and they form a crosslinked structure via A1 and A2. E1 and E2 may be the same or different. For E1 and E2, preferred are a cyclopentadienyl group, a substituted cyclopentadienyl group, an indenyl group, and a substituted indenyl group.
Specific examples of the a-bonding ligand for X3 are a halogen atom, a hydrocarbon group having from 1 to 20 carbon atoms, an alkoxy group having from 1 to 20 carbon atoms, an aryloxy group having from 6 to 20 carbon atoms, an amido group having from 1 to 20 carbon atoms, a silicon-containing group having from 1 to 20 carbon atoms, a phosphido group having from 1 to 20 carbon atoms, a sulfido group having from 1 to 20 carbon atoms, and an acyl group having from 1 to 20 carbon atoms. A plurality of X3""s, if any in formula (2), may be the same or different, and X3 may be crosslinked with other X3, E1, E2 or Y2.
Specific examples of the Lewis base for Y2 are amines, ethers, phosphines, and thioethers. A plurality of Y2""s, if any in formula (2), may be the same or different, and Y2 may be crosslinked with other Y2, E1, E2 or X3.
Preferably, at least one crosslinking group for A1 and A2 is a hydrocarbon group having at least one carbon atom. For example, the crosslinking group is represented by a general formula: 
wherein R13 and R14 each represent a hydrogen atom, or a hydrocarbon group having from 1 to 20 carbon atoms, and they may be the same or different, and may be bonded to each other to form a cyclic structure; and e indicates an integer of from 1 to 4.
Specific examples of the group are a methylene group, an ethylene group, an ethylidene group, a propylidene group, an isopropylidene group, a cyclohexylidene group, a 1,2-cyclohexylene group, and a vinylidene group (CH2xe2x95x90Cxe2x95x90). Of these, preferred are a methylene group, an ethylene group and an isopropylidene group. A1 and A2 may be the same or different.
In the transition metal compound of formula (2) where E1 and E2 each are a cyclopentadienyl group, a substituted cyclopentadienyl group, an indenyl group or a substituted indenyl group, the bond of the crosslinking group of A1 and A2 may be in the form of a double-crosslinking modeof (1, 1xe2x80x2)(2,2xe2x80x2) or in the form of a double-crosslinking mode of (1,2xe2x80x2)(2,1xe2x80x2). Of the transition metal compounds of formula (2), preferred are those having a double-crosslinked biscyclopentadienyl derivative as the ligand of the following general formula (2-a): 
In formula (2-a), M1, A1, A2, q and r have the same meanings as above. X3 represents a "sgr"-bonding ligand, and a plurality of X3""s, if any, may be the same or different, and it may be crosslinked with other X3 or Y2. For specific examples of X3, referred to are the same as those mentioned hereinabove for X3 in formula (2). Y2 represents a Lewis base, and a plurality of Y2""s, if any, may be the same or different, and it may be crosslinked with other Y2 or X3. For specific examples of Y2, referred to are the same as those mentioned hereinabove for Y2 in formula (2). R15 to R20 each represent a hydrogen atom, a halogen atom, a hydrocarbon group having from 1 to 20 carbon atoms, a halogen-containing hydrocarbon group having from 1 to 20 carbon atoms, a silicon-containing group, or a hetero atom-containing group, and at least one of them must not be a hydrogen atom. R15 to R20 may be the same or different, and the neighboring groups of them may be bonded to each other to form a ring. Preferably, the neighboring groups form an indenyl group which is substituted with an aromatic ring bonded thereto.
In the transition metal compound having such a double-crosslinked biscyclopentadienyl derivative as the ligand, the ligand may be any of a (1,1xe2x80x2)(2,2xe2x80x2) double-crosslinked one or a (1,2xe2x80x2)(2,1xe2x80x2) double-crosslinked one.
Specific examples of the transition metal compound of formula (2) are (1,1xe2x80x2-ethylene)(2,2xe2x80x2-ethylene)-bis(indenyl)zirconium dichloride, (1,2xe2x80x2-ethylene)(2,1xe2x80x2-ethylene)-bis(indenyl)zirconium dichloride, (1,1xe2x80x2-methylene)(2,2xe2x80x2-methylene)-bis(indenyl)zirconiumdichloride, (1,2xe2x80x2-methylene)(2,1xe2x80x2-methylene)-bis(indenyl)zirconium dichloride, (1,1xe2x80x2-isopropylidene)(2,2xe2x80x2-isopropylidene)-bis(indenyl)zirconium dichloride, (1,2xe2x80x2-isopropylidene)(2,1xe2x80x2-isopropylidene)-bis (indenyl)zirconium dichloride, (1,1xe2x80x2-ethylene)(2,2xe2x80x2-ethylene)-bis(3-methylindenyl)zirconium dichloride, (1,2xe2x80x2-ethylene)(2,1xe2x80x2-ethylene)-bis(3-methylindenyl)zirconium dichloride, (1,1xe2x80x2-ethylene)(2,2xe2x80x2-ethylene)-bis(4,5-benzoindenyl)zirconium dichloride, (1,2xe2x80x2-ethylene)(2,1xe2x80x2-ethylene)-bis(4,5-benzoindenyl)zirconium dichloride, (1,1xe2x80x2-ethylene)(2,2xe2x80x2-ethylene)-bis(4-isopropylindenyl)zirconium dichloride, (1,2xe2x80x2-ethylene)(2,1xe2x80x2-ethylene)-bis(4-isopropylindenyl)zirconium dichloride, (1,1xe2x80x2-ethylene)(2,2xe2x80x2-ethylene)-bis(5,6-dimethylindenyl)zirconium dichloride, (1,2xe2x80x2-ethylene(2,1xe2x80x2-ethylene)-bis(5,6-dimethylindenyl)zirconium dichloride, (1,1xe2x80x2-ethylene)(2,2xe2x80x2-ethylene)-bis(4,7-diisopropylindenyl)zirconium dichloride, (1,2xe2x80x2-ethylene)(2,1xe2x80x2-ethylene)-bis(4,7-diisopropylindenyl)zirconium dichloride, (1,1xe2x80x2-ethylene)(2,2xe2x80x2-ethylene)-bis(4-phenylindenyl)zirconium dichloride, (1,2xe2x80x2-ethylene)(2,1xe2x80x2-ethylene)-bis(4-phenylindenyl)zirconium dichloride, (1,1xe2x80x2-ethylene)(2,2xe2x80x2-ethylene)-bis(3-methyl-4-isopropylindenyl)zirconium dichloride, (1,2xe2x80x2-ethylene)(2,1xe2x80x2-ethylene)-bis(3-methyl-4-isopropylindenyl)zirconium dichloride, (1,1xe2x80x2-ethylene)(2,2xe2x80x2-ethylene)-bis(5,6-benzoindenyl)zirconium dichloride, (1,2xe2x80x2-ethylene)(2,1xe2x80x2-ethylene)-bis(5,6-benzoindenyl)zirconium dichloride, (1,1xe2x80x2-ethylene)(2,2xe2x80x2-isopropylidene)-bis(indenyl)zirconium dichloride, (1,2xe2x80x2-ethylene)(2,1xe2x80x2-isopropylidene)-bis(indenyl)zirconium dichloride, (1,1xe2x80x2-isopropylidene)(2,2xe2x80x2-ethylene)-bis(indenyl)zirconium dichloride, (1,2xe2x80x2-methylene)(2,1xe2x80x2-ethylene)-bis(indenyl)zirconium dichloride, (1,1xe2x80x2-methylene)(2,2xe2x80x2-ethylene)-bis(indenyl)zirconium dichloride, (1,1xe2x80x2-ethylene)(2,2xe2x80x2-methylene)-bis(indenyl)zirconium dichloride, (1,1xe2x80x2-methylene)(2,2xe2x80x2-isopropylidene)-bis(indenyl)zirconium dichloride, (1,2xe2x80x2-methylene)(2,1xe2x80x2-isopropylidene)-bis(indenyl)zirconium dichloride, (1,1xe2x80x2-isopropylidene)(2,2xe2x80x2-methylene)-bis(indenyl)zirconium dichloride, (1,1xe2x80x2-methylene)(2,2xe2x80x2-methylene)(3-methylcyclopentadienyl)(cyclopentadienyl)zirconium dichloride, (1,1xe2x80x2-isopropylidene)(2,2xe2x80x2-isopropylidene)(3-methylcyclopentadienyl)(cyclopentadienyl)zirconium dichloride, (1,1xe2x80x2-propylidene)(2,2xe2x80x2-propylidene)(3-methylcyclopentadienyl)(cyclopentadienyl)zirconium dichloride, (1,1xe2x80x2-ethylene)(2,2-methylene)-bis(3-methylcyclopentadienyl)zirconium dichloride, (1,1xe2x80x2methylene)(2,2xe2x80x2-ethylene)-bis(3-methylcyclopentadienyl)zirconium dichloride, (1,1xe2x80x2-isopropylidene)(2,2xe2x80x2-ethylene)-bis(3-methylcyclopentadienyl)zirconium dichloride, (1,1xe2x80x2-ethylene)(2,2xe2x80x2-isopropylidene)-bis(3-methylcyclopentadienyl)zirconium dichloride, (1,1xe2x80x2-methylene)(2,2xe2x80x2-methylene)-bis(3-methylcyclopentadienyl)zirconium dichloride, (1,1xe2x80x2-methylene)(2,2xe2x80x2-isopropylidene)-bis(3-methylcyclopentadienyl)zirconium dichloride, (1, 1xe2x80x2-isopropylidene)(2,2xe2x80x2-isopropylidene)-bis(3-methylcyclopentadienyl)zirconium dichloride, (1,1xe2x80x2-ethylene)(2,2xe2x80x2-methylene)-bis(3,4-dimethylcyclopentadienyl)zirconium dichloride, (1,1xe2x80x2-ethylene)(2,2xe2x80x2-isopropylidene)-bis(3,4-dimethylcyclopentadienyl)zirconium dichloride, (1,1xe2x80x2-methylene)(2,2xe2x80x2-methylene)-bis(3,4-dimethylcyclopentadienyl)zirconium dichloride, (1,1xe2x80x2-methylene)(2,2xe2x80x2-isopropylidene)-bis(3,4-dimethylcyclopentadienyl)zirconium dichloride, (1,1xe2x80x2-isopropylidene)(2,2xe2x80x2-isopropylidene)-bis(3,4-dimethylcyclopentadienyl)zirconium dichloride, (1,2xe2x80x2-ethylene)(2,1xe2x80x2-methylene)-bis(3-methylcyclopentadienyl)zirconium dichloride, (1,2xe2x80x2-ethylene)(2,1xe2x80x2-isopropylidene)-bis(3-methylcyclopentadienyl)zirconium dichloride, (1,2xe2x80x2-methylene)(2,1xe2x80x2-methylene)-bis(3-methylcyclopentadienyl)zirconium dichloride, (1,2xe2x80x2-methylene)(2,1xe2x80x2-isopropylidene)-bis(3-methylcyclopentadienyl)zirconium dichloride, (1,2xe2x80x2-isopropylidene)(2,1xe2x80x2-isopropylidene)-bis(3-methylcyclopentadienyl)zirconium dichloride, (1,2xe2x80x2-ethylene)(2,1xe2x80x2-methylene)-bis(3,4-dimethylcyclopentadienyl)zirconium dichloride, (1,2xe2x80x2-ethylene)(2,1xe2x80x2-isopropylidene)-bis(3,4-dimethylcyclopentadienyl)zirconium dichloride, (1,2xe2x80x2-methylene)(2,1xe2x80x2-methylene)-bis(3,4-dimethylcyclopentadienyl)zirconium dichloride, (1,2xe2x80x2-methylene)(2,1xe2x80x2-isopropylidene)-bis(3,4-dimethylcyclopentadienyl)zirconium dichloride, (1,2xe2x80x2-isopropylidene)(2,1xe2x80x2-isopropylidene)-bis(3,4-dimethylcyclopentadienyl)zirconium dichloride, (1,2xe2x80x2-ethylene)(2,1xe2x80x2-ethylene)-bis(5,5-phenylindenyl)zirconium dichloride, (1,2xe2x80x2-ethylene)(2,1xe2x80x2-ethylene-bis(5,6-phenylindenyl)zirconium dichloride, (1,2xe2x80x2-ethylene)(2,1xe2x80x2-ethylene)-bis(6,6-phenylindenyl)zirconium dichloride, and their derivatives derived from the compounds by substituting the zirconium therein with titanium or hafnium; as well as dimethylsilylene(1-(2-methyl-4,5-benzoindenyl))(2-indenyl)zirconium dichloride, dimethylsilylene(1-(2-ethyl-4,5-benzoindenyl))(2-indenyl)zirconium dichloride, dimethylsilylene(l-(2-butyl-4,5-benzoindenyl))(2-indenyl)zirconium dichloride, dimethylsilylene(1-(2-methyl-4,5-benzoindenyl))(2-4,7-dimethylindenyl)zirconium dichloride, dimethylsilylene(1-(2-ethyl-4,5-benzoindenyl))(2-4,7-dimethylindenyl)zirconium dichloride, diphenylsilylene(1-(2-methyl-4,5-benzoindenyl))(2-indenyl)zirconium dichloride, diphenylsilylene(1-(2-ethyl-4,5-benzoindenyl))(2-indenyl)zirconium dichloride, diphenylsilylenesilylene(1-(2-butyl-4,5-benzoindenyl))(2-indenyl)zirconium dichloride, diphenylsilylene(1-(2-methyl-4,5-benzoindenyl))(2-4,7-dimethylindenyl)zirconium dichloride, diphenylsilylene(1-(2-ethyl-4,5-benzoindenyl))(2-4,7-dimethylindenyl)zirconium dichloride, and their derivatives with hafnium and not zirconium. Needless-to-say, the invention is not limited to these compounds. For the component (A-2), two or more of these transition metal compounds may be combined.
For the component (A) of the olefin polymerization catalyst to be used in the invention, preferred is the component (A-1).
Next described is the component (B).
The component (B) for use in the invention is at least one selected from (B-1) aluminiumoxy compounds and (B-2) ionic compounds capable of reacting with the transition metal compound to give cations.
The aluminiumoxy compounds for the component (B-1) include linear aluminoxanes of the following general formula (3): 
wherein R21 represents a hydrocarbon group, such as an alkyl, alkenyl, aryl, arylalkyl or the like group having from 1 to 20, preferably from 1 to 12 carbon atoms, or a halogen atom; w indicates a degree of mean polymerization, and is an integer generally falling between 2 and 50, preferably between 2 and 40; and plural R21""s may be the same or different, and cyclic aluminoxanes of the following general formula (4): 
wherein R21 and w have the same meanings as in formula (3).
Concretely, they include methylaluminoxane, ethylaluminoxane and isobutylaluminoxane.
For producing the aluminoxanes, an alkylaluminium may be contacted with a condensation agent such as water or the like, for which the mode of condensation is not specifically defined and the reactants may be reacted in any ordinary manner. For it, for example, employable is (1) a method comprising dissolving an organoaluminium compound in an organic solvent followed by contacting it with water; (2) a method comprising directly adding an organoaluminium compound to the polymerization system that requires the intended aluminoxane, followed by adding water thereto; (3) a method comprising reacting an organoaluminium compound with crystal water existing in metal salts and the like or with water having adsorbed by inorganic or organic substances; or (4) a method comprising reacting a tetraalkyldialuminoxane with a trialkylaluminium and then with water.
The aluminoxanes may be insoluble or soluble in hydrocarbon solvents. Preferably, however, they are soluble in hydrocarbon solvents and the residual organoaluminium compound therein measured through 1H-NMR accounts for at most 10% by weight, more preferably from 3 to 5% by weight, even more preferably from 2 to 4% by weight. One advantage of the aluminoxanes of that type is that the proportion of the aluminoxane capable of being held on a carrier (this may be referred to as an on-carrier percentage of the compound) high. Another advantage of the aluminoxanes soluble in hydrocarbon solvents is that their part not held on a carrier can be recycled. Still another advantage is that they do not require any specific treatment before use since their properties are stable. Still another advantage is that the morphology (including the mean particle size and the particle size distribution) of the polyolefins produced through polymerization in the presence of the aluminoxane of that type is good. If the residual organoaluminium compound in aluminoxanes accounts for more than 10% by weight, it is unfavorable since the on-carrier percentage of the aluminoxane will decrease and the polymerization activity thereof will thereby decrease.
For obtaining the aluminoxanes of that type, for example, employable is a method that comprises drying up an aluminoxane solution to completely remove the solvent from it through distillation to dryness under heat under reduced pressure (this is referred to as a drying-up method). In the drying-up method under heat under reduced pressure, it is desirable that the solvent is evaporated away at a temperature not higher than 80xc2x0 C., more preferably not higher than 60xc2x0 C.
The fraction not soluble in hydrocarbon solvents may be removed from the aluminoxanes. For removing it, for example, employable is a method that comprises processing the aluminoxane in a hydrocarbon solvent to lead to spontaneous precipitation of the fraction not soluble in the solvent, followed by removing the insoluble fraction through decantation. Another method comprises removing the insoluble fraction through centrifugation or the like. More preferably, the thus-recovered, soluble fraction is filtered through a G5 glass filter or the like in a nitrogen atmosphere, whereby the insoluble fraction is more completely removed from it. The thus-processed aluminoxane will have an increased amount of a gelled fraction with the lapse of time. Therefore, it is desirable that the organoaluminoxane is used within 48 hours after its preparation, more preferably immediately after its preparation. The ratio of the organoaluminoxane to the hydrocarbon solvent is not specifically defined, but it is desirable that the amount of the organoaluminoxane falls between 0.5 and 10 mols in terms of the aluminium atom in the compound relative to 1 liter of the hydrocarbon solvent.
The hydrocarbon solvents include, for example, aromatic hydrocarbons such as benzene, toluene, xylene, cumene, cymene; aliphatic hydrocarbons such as pentane, hexane, heptane, octane, decane, dodecane, hexadecane, octadecane; alicyclic hydrocarbons such as cyclopentane, cyclohexane, cyclooctane, methylcyclopentane; petroleum fractions such as naphtha, kerosene, light gas oil.
One or more of these aluminoxanes may be used herein either singly or as combined.
For the component (B-2), usable are any ionic compounds capable of reacting with the above-mentioned transition metal compound to give cations. Especially preferred are ionic compounds of the following formulae (5) and (6), as they can efficiently form polymerization active points.
([L1xe2x80x94R22]h+)a([Z]xe2x88x92)bxe2x80x83xe2x80x83(5)
([L2]h+)a([Z]xe2x88x92)bxe2x80x83xe2x80x83(6)
wherein L2 indicates M2, R23R24M3, R253C or R26M3.
In formulae (5) and (6), L1 indicates a Lewis base; [Z]xe2x88x92 indicates a non-coordinating anion [Z1]xe2x88x92 or [Z2]xe2x88x92; [Z1]xe2x88x92 is an anion with a plurality of groups bonded to an element, and it may be represented by [M4G1G2 . . . Gf] wherein M4 is an element of Groups 5 to 15 of the Periodic Table, preferably an element of Groups 13 to 15 of the Periodic Table; G1 to Gf each indicate a hydrogen atom, a halogen atom, an alkyl group having from 1 to 20 carbon atoms, a dialkylamino group having from 2 to 40 carbon atoms, an alkoxy group having from 1 to 20 carbon atoms, an aryl group having from 6 to 20 carbon atoms, an aryloxy group having from 6 to 20 carbon atoms, an alkylaryl group having from 7 to 40 carbon atoms, an arylalkyl group having from 7 to 40 carbon atoms, a halogen-substituted hydrocarbon group having from 1 to 20 carbon atoms, an acyloxy group having from 1 to 20 carbon atoms, an organometalloid group, or a hetero atom-containing hydrocarbon group having from 2 to 20 carbon atoms; and two or more of G1 to Gf may form a ring; f is an integer, indicating [(valence of the center metal M4)+1]; [Z2]xe2x88x92 is a conjugated base of a Brxc3x8nsted acid, of which the logarithmic number (pKa) of the reciprocal of the acid dissociation constant is not larger than xe2x88x9210, alone or a combination of such a Brxc3x8nsted acid and a Lewis acid, or is a conjugated base which is generally defined as an ultra-strong acid, and it may be coordinated with a Lewis base; R22 indicates a hydrogen atom, an alkyl group having from 1 to 20 carbon atoms, an aryl group having from 6 to 20 carbon atoms, an alkylaryl group having from 7 to 40 carbon atoms, or an arylalkyl group having from 7 to 40 carbon atoms; R23 and R24 each indicate a cyclopentadienyl group, a substituted cyclopentadienyl group, an indenyl group, or a fluorenyl group; R24 indicates an alkyl group having from 1 to 20 carbon atoms, an aryl group having from 6 to 20 carbon atoms, an alkylaryl group having from 7 to 40 carbon atoms, or an arylalkyl group having from 7 to 40 carbon atoms; R26 indicates a macrocyclic ligand such as tetraphenylporphyrin or phthalocyanine; h is an integer of from 1 to 3, indicating the ion valence of [L1xe2x80x94R22] or [L2]; a is an integer of at least 1; b=(hxc3x97a); M2 includes elements of Groups 1 to 3, 11 to 13 and 17 of the Periodic Table; and M3 indicates an element of Groups 7 to 12 of the Periodic Table.
Specific examples of L1 are ammonia; amines such as methylamine, aniline, dimethylamine, diethylamine, N-methylaniline, diphenylamine, N,N-dimethylaniline, trimethylamine, triethylamine, tri-n-butylamine, methyldiphenylamine, pyridine, p-bromo-N,N-dimethylaniline, p-nitro-N,N-dimethylaniline; phosphines such as triethylphosphine, triphenylphosphine, diphenylphosphine; thioethers such as tetrahydrothiophene; esters such as ethyl benzoate; and nitriles such as acetonitrile, benzonitrile.
Specific examples of R22 are a hydrogen atom, a methyl group, an ethyl group, a benzyl group and a trityl group; specific examples of R23 and R24 are a cyclopentadienyl group, a methylcyclopentadienyl group, an ethylcyclopentadienyl group, and a pentamethylcyclopentadienyl group. Specific examples of R25 are a phenyl group, a p-tolyl group, and a p-methoxyphenyl group. Specific examples of R26 are tetraphenylporphyrin, phthalocyanine, allyl and methallyl. Specific examples of M2 are Li, Na, K, Ag, Cu, Br, I, and I3. Specific examples of M3 are Mn, Fe, Co, Ni, and Zn.
Specific examples of M4 in [M4G1G2 . . . Gf] for [Z1]xe2x88x92 are B, Al, Si, P, As and Sb. Preferred are B and Al. Specific examples of G1, G2 to Gf are a dialkylamino group such as dimethylamino and diethylamino groups; an alkoxy or aryloxy group such as methoxy, ethoxy, n-butoxy and phenoxy groups; a hydrocarbon group such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-octyl, n-eicosyl, phenyl, p-tolyl, benzyl, 4-t-butylphenyl and 3,5-dimethylphenyl groups; a halogen atom such as fluorine, chlorine, bromine and iodine atoms; a hetero atom-containing hydrocarbon group such as p-fluorophenyl, 3,5-difluorophenyl, pentachlorophenyl, 3,4,5-trifluorophenyl, pentafluorophenyl, 3,5-bis(trifluoromethyl)phenyl, and bis(trimethylsilyl)methyl groups; an organometalloid group such as pentamethylantimonyl, trimethylsilyl, trimethylgermyl, diphenylarsenyl, dicyclohexylantimonyl and diphenylboryl groups.
Specific examples of the non-coordinating anion, [Z2]xe2x88x92, which is a conjugated base of a Brxc3x8nsted acid having pKa of at most xe2x88x9210 alone or a combination of such a Brxc3x8nsted acid and a Lewis acid, are trifluoromethanesulfonate anion (CF3SO3)xe2x88x92, bis(trifluoromethanesulfonyl)methyl anion, bis(trifluoromethanesulfonyl)benzyl anion, bis(trifluoromethanesulfonyl)amido anion, perchlorate anion (ClO4)xe2x88x92, trifluoroacetate anion (CF3CO2)xe2x88x92, hexafluoroantimonyl anion (SbF6)xe2x88x92, fluorosulfonate anion (FSO3)xe2x88x92, chlorosulfonate anion (ClSO3)xe2x88x92, fluorosulfonate anion/pentafluoroantimony (FSO3/SbF5)xe2x88x92, fluorosulfonate anion/pentafluoroarsenic (FSO3/AsF5)xe2x88x92, and trifluoromethanesulfonate anion/pentafluoroantimony (CF3SO3/SbF5)xe2x88x92.
Specific examples of the compounds for the component (B-2) are triethylammonium tetraphenylborate, tri-n-butylammonium tetraphenylborate, trimethylammonium tetraphenylborate, tetraethylammonium tetraphenylborate, methyl(tri-n-butyl)ammonium tetraphenylborate, benzyl(tri-n-butyl)ammonium tetraphenylborate, dimethyldiphenylammonium tetraphenylborate, trimethyl(methyl)ammonium tetraphenylborate, trimethylanilinium tetraphenylborate, methylpyridinium tetraphenylborate, benzylpyridinium tetraphenylborate, methyl(2-cyanopyridinium)tetraphenylborate, triethylammonium tetrakis(pentafluorophenyl)borate, tri-n-butylammonium tetrakis(pentafluorophenyl)borate, triphenylammonium tetrakis(pentafluorophenyl)borate, tetra-n-butylammonium tetrakis(pentafluorophenyl)borate, tetraethylammonium tetrakis(pentafluorophenyl)borate, benzyl(tri-n-butyl)ammonium tetrakis(pentafluorophenyl)borate, methyldiphenylammonium tetrakis(pentafluorophenyl)borate, triphenyl(methyl)ammonium tetrakis(pentafluorophenyl)borate, methylanilinium tetrakis(pentafluorophenyl)borate, dimethylanilinium tetrakis(pentafluorophenyl)borate, trimethylanilinium tetrakis(pentafluorophenyl)borate, methylpyridinium tetrakis(pentafluorophenyl)borate, benzylpyridinium tetrakis(pentafluorophenyl)borate, methyl(2-cyanopyridinium)tetrakis(pentafluorophenyl)borate, benzyl(2-cyanopyridinium)tetrakis(pentafluorophenyl)borate, methyl(4-cyanopyridinium)tetrakis(pentafluorophenyl)borate, triphenylphosphonium tetrakis(pentafluorophenyl)borate, dimethylanilinium tetrakis[bis(3,5-ditrifluoromethyl)phenyl]borate, ferrocenium tetraphenylborate, silver tetraphenylborate, trityl tetraphenylborate, tetraphenylporphyrin-manganese tetraphenylborate, ferrocenium tetrakis(pentafluorophenyl)borate, (1,1xe2x80x2-dimethylferrocenium)tetrakis(pentafluorophenyl)borate, decamethylferrocenium tetrakis(pentafluorophenyl)borate, silver tetrakis(pentafluorophenyl)borate, trityl tetrakis(pentafluorophenyl)borate, lithium tetrakis(pentafluorophenyl)borate, sodium tetrakis(pentafluorophenyl)borate, tetraphenylporphyrin-manganese tetrakis(pentafluorophenyl)borate, silver tetrafluoroborate, silver hexafluorophosphate, silver hexafluoroarsenate, silver perchlorate, silver trifluoroacetate, and silver trifluoromethanesulfonate. For the component (B-2), preferred are the ionic compounds of formula (5).
For the component (B-2), one or more of the ionic compounds capable of reacting with the transition metal compound of the component (A) to give cations may be used herein either singly or as combined.
In the olefin polymerization catalyst for use in the invention, the component (B) may be the component (B-1) alone or the component (B-2) alone, or may also be a combination of the components (B-1) and (B-2).
The catalyst may comprise, as the essential ingredients, the components (A) and (B), or may comprise, as the essential ingredients the components (A) and (B) and an additional component (C) of an organoaluminium compound.
The organoaluminium compound for the component (C) may be represented by a general formula (7):
R27vAlQ3-vxe2x80x83xe2x80x83(7)
wherein R27 indicates an alkyl group having from 1 to 10 carbon atoms; Q indicates a hydrogen atom, an alkoxy group having from 1 to 20 carbon atoms, an aryl group having from 6 to 20 carbon atoms, or a halogen atom; and v is an integer of from 1 to 3.
Specific examples of the compound of formula (7) are trimethylaluminium, triethylaluminium, triisopropylaluminium, triisobutylaluminium, dimethylaluminium chloride, diethylaluminium chloride, methylaluminium dichloride, ethylaluminium dichloride, dimethylaluminium fluoride, diisobutylaluminium hydride, diethylaluminium hydride, and ethylaluminium sesqui-chloride.
One or more of these organoaluminium compounds may be used herein either singly or as combined.
Regarding the ratio of the catalyst component (A) and the catalyst component (B) that constitute the polymerization catalyst, the molar ratio of the component (A) to the compound (B-1) for the component (B) preferably falls between 1/1 and 1/106, more preferably between 1/10 and 1/104. If the ratio oversteps the defined range, the catalyst cost per the unit weight of the polymer to be produced will be high, and it is impracticable. The molar ratio of the component (A) to the compound (B-2) for the component (B) preferably falls between 10/1 and 1/100, more preferably between 2/1 and 1/10, to the component (A). If the ratio oversteps the defined range, the catalyst cost per the unit weight of the polymer to be produced will be high, and it is impracticable.
The molar ratio of the catalyst component (A) to the optional catalyst component (C) preferably falls between 1/1 and 1/20,000, more preferably between 1/5 and 1/2,000, even more preferably between 1/10 and 1/1,000. The catalyst component (C), if used, enhances the polymerization activity per the transition metal of the catalyst. However, if the component (C) is too much, especially overstepping the defined range, the organoaluminium compound used shall be wasted, and will much remain in the polymer produced; but if too small, it will be often unfavorable since the catalyst activity will be poor.
In the invention, at least one catalyst component may be held on a suitable carrier. The carrier is not specifically defined, and may be any of inorganic oxides, and even other inorganic substances and organic substances. For well controlling the morphology of the polymer to be produced, preferred are inorganic oxide carriers and other inorganic carriers. Concretely, the inorganic oxide carriers include SiO2, Al2O3, MgO, ZrO2, TiO2, Fe2O3, B2O3, CaO, ZnO, BaO, ThO2, and their mixtures, for example, silica-alumina, zeolite, ferrite, and glass fibers. Of those, especially preferred are SiO2 and Al2O3. The inorganic oxide carriers may contain minor carbonates, nitrates and sulfates. In addition to the carriers mentioned above, also usable herein are other carriers of magnesium compounds of a general formula MgR28xX4y, such as MgCl2 and Mg(OC2H5)2, and their complexes. In the formula, R28 represents an alkyl group having from 1 to 20 carbon atoms, an alkoxy group having from 1 to 20 carbon atoms, or an aryl group having from 6 to 20 carbon atoms; X4 represents a halogen atom, or an alkyl group having from 1 to 20 carbon atoms; x falls between 0 and 2, y falls between 0 and 2, and x+y=2. Plural R28""s and plural X4""s may be the same or different. The organic carriers usable herein include polymers such as polystyrenes, styrene-divinylbenzene copolymers, polyethylenes, polypropylenes, substituted polystyrenes, polyarylates; as well as starch and carbon. Preferred carriers for use in the invention are MgCl2, MgCl(OC2H5), Mg(OC2H5)2, SiO2 and Al2O3. The properties of the carriers vary, depending on their type and the method for producing them. The carriers will have a mean pore size generally falling between 1 and 300 xcexcm, but preferably between 10 and 200 xcexcm, more preferably between 20 and 100 xcexcm. If the particle size of the carrier used is too small, the fine powder content of the polymer produced will increase; but if too large, the coarse particles in the polymer will increase, and they lower the bulk density of the polymer and will clog hoppers. The specific surface area of the carrier may fall generally between 1 and 1,000 m2/g, but preferably between 50 and 500 m2/g; and the pore volume thereof may fall generally between 0.1 to 5 cm3/g, but preferably between 0.3 and 3 cm3/g. If any of the specific surface area and the pore volume of the carrier oversteps the defined range, the catalyst activity will be low. The specific surface area and the pore volume of the carrier may be derived from the volume of the nitrogen gas having been absorbed by the carrier, for example, according to the BET method (see J. Am. Chem. Soc., Vol. 60, p. 309 (1983)). Preferably, the carrier is baked at a temperature falling between 150 and 1,000xc2x0 C., more preferably between 200 and 800xc2x0 C., before it is used herein.
When at least one catalyst component is held on the carrier, it is desirable that at least one of the catalyst component (A) and the catalyst component (B), more preferably both the components (A) and (B) are held thereon for ensuring good morphology control of the polymer to be produced and for ensuring good applicability of the catalyst to vapor-phase polymerization to give the polymer.
The method for holding at least one of the components (A) and (B) on a carrier such as that mentioned above is not specifically defined. For example, (1) at least one of the components (A) and (B) may be mixed with a carrier; (2) a carrier is first processed with an organoaluminium compound or a halogen-containing silicon compound (e.g., silicon tetrachloride, methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane), and this is then mixed with at least one of the components (A) and (B) in an inert solvent; (3) a carrier is, along with either one or both of the components (A) and (B), reacted with an organoaluminium compound or a halogen-containing silicon compound (e.g., silicon tetrachloride, methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane); (4) the component (A) or (B) is held on a carrier, and this is then mixed with the other component (B) or (A); (5) a product prepared by contacting the components (A) and (B) with each other is mixed with a carrier; or (6) the components (A) and (B) are contacted with each other in the presence of a carrier. In the methods (4), (5) and (6), an organoaluminium compound may be optionally added to the system. The organoaluminium compound may be selected from those for the component (C) mentioned hereinabove.
In the method (4), (5) and (6), the organoaluminium compound for the component (C) may be optionally added to the system.
In the invention, the ratio of the component (B-1) to the carrier preferably falls between 1/0.5 and 1/1,000, more preferably between 1/1 and 1/50 by weight; and the ratio of the component (B-2) to the carrier preferably falls between 1/5 and 1/10,000, more preferably between 1/10 and 1/500 by weight. When the catalyst component (B) is a mixture of two or more compounds, it is desirable that the ratio by weight of each compound to the carrier falls within the defined range. The ratio of the component (A) to the carrier preferably falls between 1/5 and 1/10,000, more preferably between 1/10 and 1/500 by weight.
If the ratio of the component (B) (component (B-1), component (B-2)) to the carrier, or the ratio of the component (A) to the carrier oversteps the defined range, the catalyst activity will be low. The mean particle size of the polymerization catalyst thus prepared herein for use in the invention may fall generally between 2 and 200 xcexcm, but preferably between 10 and 150 xcexcm, more preferably between 20 and 100 xcexcm; and the specific surface area thereof may fall generally between 20 and 1,000 m2/g, but preferably between 50 and 500 m2/g. If the mean particle size of the catalyst is smaller than 2 xcexcm, fine powder in the polymer produced will increase; but if larger than 200 xcexcm, coarse particles therein will increase. If the specific surface area of the catalyst is smaller than 20 m2/g, the catalyst activity will be low; but if larger than 1,000 m2/g, the bulk density of the polymer produced will be low. The transition metal content of the polymerization catalyst may fall generally between 0.001 and 1 g, but preferably between 0.001 and 0.1 g per 100 g of the carrier in the catalyst. If the transition metal content oversteps the defined range, the catalyst activity will be low. With the catalyst held on the carrier, olefin polymers having a high bulk density and a desired particle size distribution can be obtained, and they are favorable to industrial use.
The component (A), the component (B) and optionally the component (C) and/or a carrier may be contacted with each other in an inert gas such as nitrogen, in a hydrocarbon solvent such as pentane, hexane, heptane, toluene or cyclohexane. The temperature at which they are contacted with each other may fall between xe2x88x9230xc2x0 C. and the boiling point of the solvent used, but preferably between xe2x88x9210xc2x0 C. and 100xc2x0 C., and the time for their contact may fall generally between 30 seconds and 10 hours. After having been thus contacted with each other, the resulting solid catalyst component may be or may not be washed. In the contact treatment, any of the two different types of transition metal compounds for the component (A) may be used previously to the other, or the two may be mixed before they are contacted with other components.
The catalyst thus prepared may be subjected to solvent removal from it, and the resulting solid may be used for polymerization; or it may be directly used for polymerization as it is.
In the invention, if desired, the treatment of contacting at least one of the component (A) and the component (B) with a carrier so that it is held on the carrier may be effected in a polymerization system. In this case, the intended catalyst is formed in the polymerization system. For example, at least one of the component (A) and the component (B), and a carrier and optionally an organoaluminium compound for the component (C) are added to a polymerization system in which an olefin is pre-polymerized to give the intended catalyst. The olefin for pre-polymerization may be any of ethylene and xcex1-olefins having from 3 to 20 carbon atoms, such as propylene, 1-butene-, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene and 1-tetradecene. Of those, preferred are ethylene and propylene optionally combined with an xcex1-olefin to be used in ethylene-propylene polymerization. The pre-polymerization may be effected in an inert hydrocarbon solvent. Concretely, the solvent may be the same as that used in preparing the solid catalyst component. The amount of the catalyst component to be pre-polymerized may fall generally between 10xe2x88x926 and 2xc3x9710xe2x88x922 mols/liter (solvent), but preferably between 5xc3x9710xe2x88x925 and 10xe2x88x922 mols/liter (solvent) in terms of the transition metal in the component. In one gram of the carrier used, the atomic ratio of aluminium in the organoaluninium compound such as methylaluminoxane (this is referred to as MAO) to the transition metal in thecatalyst component, Al/transition metal, may fall generally between 10 and 5,000, but preferably between 20 and 1,000. The atomic ratio of the aluminium atom in the organoaluminium compound optionally used herein to the aluminium atom in MAO may fall generally between 0.02 and 3, but preferably between 0.05 and 1.5. The temperature for the pre-polymerization may fall between xe2x88x9220 and 60xc2x0 C., but preferably between 0 and 50xc2x0 C. The time for the pre-polymerization may fall between 0.5 and 100 hours, but preferably between 1 and 50 hours or so. In the invention, it is desirable that the catalyst is prepared through such olefin pre-polymerization.
Next described is a method of using the polymerization catalyst prepared in the manner as above in propylene homopolymerization or propylene copolymerization with ethylene and/or an xcex1-olefin having from 4 to 20 carbon atoms.
The polymerization method is not specifically defined, to which is applicable any mode of slurry polymerization, vapor-phase polymerization, bulk polymerization, solution polymerization or suspension polymerization. However, preferred are slurry polymerization and vapor-phase polymerization; and more preferred is vapor-phase polymerization.
The polymerization condition is described. The polymerization temperature may fall generally between xe2x88x92100 and 250xc2x0 C., but preferably between xe2x88x9250 and 200xc2x0 C., more preferably between 0 and 130xc2x0 C. The ratio of the starting monomer to the catalyst preferably falls between 1 and 108, more preferably between 100 and 105, in terms of the molar ratio of monomer/component (A). The polymerization time may fall generally between 5 minutes and 10 hours; and the reaction pressure preferably falls between normal pressure and 20 MPaxc2x7G, more preferably between normal pressure and 10 MPaxc2x7G.
For controlling the molecular weight of the polymers to be produced, the type and the amount of the catalyst components to be used and the polymerization temperature will be suitably selected. If desired, hydrogen may be introduced into the polymerization system for that purpose.
The polymerization solvent, if used, includes aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene; alicyclic hydrocarbons such as cyclopentane, cyclohexane, methylcyclohexane; aliphatic hydrocarbons such as pentane, hexane, heptane, octane; and halogenohydrocarbons such as chloroform, dichloromethane. One or more such solvents may be used either singly or as combined. As the case may be, the starting monomers such as xcex1-olefins will act also as the solvent. In some polymerization modes, no solvent will be used.
Prior to polymerization, the polymerization catalyst may be subjected to pre-polymerization. For pre-polymerizing it, for example, a small amount of an olefin may be contacted with the solid catalyst component, and the method of pre-polymerization is not specifically defined and may be effected in any known manner. The olefin to be used in the pre-polymerization is not specifically defined, and any one mentioned hereinabove may be used. For example, usable are ethylene, xcex1-olefins having from 3 to 20 carbon atoms, and their mixtures. However, it is desirable that the olefin for the pre-polymerization is the same as that for the final polymerization to give final polymers.
The temperature for the pre-polymerization may fall generally between xe2x88x9220 and 200xc2x0 C., but preferably between xe2x88x9210 and 130xc2x0 C., more preferably between 0 and 80xc2x0 C. A solvent may be used for the pre-polymerization, and it includes inert hydrocarbons, aliphatic hydrocarbons, aromatic hydrocarbons, and monomers. Of those, especially preferred are aliphatic hydrocarbons. As the case may be, the pre-polymerization may be effected in the presence of no solvent.
Preferably, the pre-polymerization condition is so controlled that the pre-polymerization product has an intrinsic viscosity [xcfx81] (measured in tetralin at 135xc2x0 C.) of at least 0.2 dl/g, more preferably at least 0.5 dl/g, and that the amount of the pre-polymerization product falls between 1 and 10,000 g, more preferably between 10 and 1,000 g, relative to one mmol of the transition metal component in the catalyst.
In co-polymerization, the order of feeding the starting monomers to the reactor is not specifically defined. Preferably, however, xcex1-olefins are fed thereto prior to propylene thereto. When ethylene is co-polymerized with propylene, it is desirable that a mixed gas of propylene and ethylene is fed to the reactor. The amount of the comonomer to be used is as follows: When an xcex1-olefin is used as the comonomer, its amount falls between 1 and 10,000,000 mols, preferably between 1 and 1,000,000 mols, more preferably between 1 and 100,000 mols per mol of the catalyst. For ethylene, the molar ratio of ethylene/propylene falls between 0.01/100 and 99/100, preferably between 0.01/100 and 55/100, more preferably between 0.01/100 and 10/100.
3. Moldings:
The moldings of the invention are obtained by molding the propylene polymer mentioned hereinabove. The moldings of the invention are characterized in that they are flexible and their low-temperature workability (especially, low-temperature heat-sealability, embossing processability) is good. In addition, they are highly transparent. The moldings of the invention include films, sheets, fibers, containers, automobile trims, housings for electric and electronic appliances for household use, etc. Above all, they are favorable to films and sheets. As having good low-temperature heat-sealability, the films are favorable, for example, for wrapping and packaging edibles and for agricultural use (for example, for hothouses). As highly transparent, the containers are favorable to transparent cases, transparent boxes, decorative boxes, etc.
For forming the moldings, employable is any method of injection molding, compression molding, injection compression molding, gas-assisted injection molding, extrusion, blow molding, calender molding, etc. For forming films and sheets, usable is any of compression molding, extrusion, blow molding or casting.
The invention is described in more detail with reference to the following Examples, which, however, are not intended to restrict the scope of the invention.
First described are the methods for analyzing and evaluating the polymers produced and their resin characteristics and physical properties.
(1) Measurement of [xcfx81]:
Using a Rigo""s automatic viscometer, VMR-053 Model, each sample is measured in a solvent of tetralin at 135xc2x0 C.
(2) Measurement of Pentad Fraction and Abnormal Insert Fraction:
Measured according to the method described in the section of the detailed description of the invention.
(3) Comonomer Content and Stereospecificity Index [mm] of Copolymer:
Using a JEOL""s NMR apparatus, JNM-EX400 Model, each sample is subjected to 13C-NMR spectrometry under the condition mentioned below, and its data are analyzed according to the methods mentioned below.
Sample concentration: 220 mg/3 ml of NMR solvent
NMR solvent: 1,2,4-trichlorobenzene/benzene-d6 (90/10 vol. %)
Temperature: 130xc2x0 C.
Pulse width: 45xc2x0
Pulse frequency: 4 seconds
Frequency integration: 10,000 times
(a) 1-butene Content:
The 13C-NMR spectral chart of a random copolymer of propylene and 1-butene is analyzed for the chemical shift of each signal and its assignment. The data are in Table 1.
The 1-butene unit content, xcex1 (mol %), of the copolymer is obtained according to the following formula (1), based on the main-chain methylene carbon.
xcex1={[(2)/2 +(4)]/[(1)+(2)+(3)+(4)+2xc3x97(9)]}xc3x97100xe2x80x83xe2x80x83(1)
The signal intensity of No. 1, 2, . . . in Table 1 is substituted for (1), (2) . . . in formula (1).
The stereospecificity index [mm] of the copolymer is obtained according to the following formula (2), based on the signal intensity of Nos. 12 to 14 in Table 1. This indicates the isotactic triad fraction of the PPP chain in the head-tail bonded site of the copolymer.
P={(12)/[(12)+(13)+(14)]}xc3x97100xe2x80x83xe2x80x83(2)
The signal intensity of the PPP chain Sxcex1xcex2 carbon is substituted for the signal of the PPP chain Sxcex1xcex2 carbon.
(4) Measurement of Molecular Weight Distribution (Mw/Mn):
Using the GPC apparatus mentioned below, the weight-average molecular weight Mw and the number-average molecular weight Mn of the polymer are measured in terms of polyethylene, under the condition mentioned below. From the data, obtained is Mw/Mn of the polymer.
GPC apparatus:
Column: TOSO GMHHR-H(S)HT
Detector: RI detector for liquid chromatography, WATERS 150C
Condition:
Solvent: 1,2,4-trichlorobenzene
Temperature: 145xc2x0 C.
Flow rate: 1.0 ml/min
Sample concentration: 2.2 mg/ml
Amount of sample injected: 160 xcexcl
Calibration curve: Universal Calibration
Program for analysis: HT-GPC (Ver. 10)
(5) DSC:
A differential scanning calorimeter (Parkin Elmer""s DSC-7) is used. 10 mg of a sample is melted at 230xc2x0 C. in a nitrogen atmosphere for 3 minutes, then cooled to 0xc2x0 C. at a cooling rate of 10xc2x0 C./min, kept at 0xc2x0 C. for 3 minutes, and thereafter again heated at a heating rate of 10xc2x0 C./min. The endothermic heat of fusion of the sample is represented by xcex94H. The temperature at which the endothermic fusion curve of the sample gives the peak top is read, and this indicates the melting point, Tm (xc2x0 C.) of the sample.
(6) Programmed-temperature Fractionation Chromatography:
In the manner mentioned below, the sample is subjected to TREF to obtain its elution curve. In the elution curve, the amount of the eluate fraction (% by weight) of the sample not adsorbed by the filler in the column at 25xc2x0 C. is read.
(a) Process:
A solution of the sample is introduced into the TREF column conditioned at 135xc2x0 C., then gradually cooled to 0xc2x0 C. at a cooling rate of 5xc2x0 C./hr, and kept as it is for 30 minutes so that the sample is adsorbed by the filler in the column. Next, this is heated up to 135xc2x0 C. at a heating rate of 40xc2x0 C./hr. This heat cycle gives an elution curve of the sample. The temperature of the peak top of the elution curve is read, and this is Tp. The amount of the fraction of the sample having been eluted within a temperature range of Tpxc2x15xc2x0 C. is obtained. The half-value width of the peak top of the elution curve is obtained, and this is Th (xc2x0 C.).
(b) Apparatus:
TREF column: GL Science""s silica gel column (4.6xc3x8xc3x97150 mm)
Flow cell: GL Science""s KBr cell with an optical path of 1 mm
Feed pump: Senshu Science""s SSC-3100 pump
Valve oven: GL Science""s Model 554 oven (high-temperature type)
TREF oven: GL Science""s TREF oven
Dual thermostat: Rigaku IndustryIs REX-C100 thermostat
Detector: IR detector for liquid chromatography, Foxboro""s MIRAN 1A CVF
10-way valve: Balco""s electric valve
Loop: Balcols 500-xcexcl loop
(c) Condition:
Solvent: o-dichlorobenzene
Sample concentration: 7.5 g/liter
Amount of sample injected: 500 xcexcl
Pump flow rate: 2.0 ml/min
Wavelength for detection: 3.41 xcexcm
Column filler: Chromosorb P (30 to 60 mesh)
Column temperature profile: within xc2x10.2xc2x0 C.
(7) Tensile Modulus:
The propylene polymer produced is press-molded into test pieces. The tensile modulus of the test piece is measured in a tensile test according to JIS K7113.
Thickness of test piece (#2 dumbbell): 1 mm
Cross head speed: 50 mm/min
Load cell: 100 kg
(8) Internal Haze:
The propylene polymer produced is press-molded into test pieces. The test piece is tested for its internal haze according to JIS K7105.
Test piece: 15 cmxc3x9715 cmxc3x971 mm (thickness: 1 mm)
(9) Measurement of Boiling Diethyl Ether Extract:
Using a Soxhlet extractor, the sample is extracted under the condition mentioned below.
Sample: 1 to 2 g
Sample morphology: powder (pellets are powdered)
Extraction solvent: diethyl ether
Extraction time: 10 hours
Extraction frequency: at least 180 times
The boiling diethyl ether extract of the sample is obtained according to the following formula:
[diethyl ether extract (g)/amount of powdery sample (g)]xc3x97100